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arXiv · 2607.11080

Distance Estimates to Five Bok Globules Using Gaia DR3 Parallaxes and Near-Infrared Photometry: Validation with 3D Dust Maps

Rajat Subhra Paul·Himadri Sekhar Das
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Abstract

Accurate distances to small, opaque Bok globules are difficult to obtain due to their compact sizes and lack of embedded standard candles. We estimate distances to five globules -- CB4, CB24, CB56, CB60, and CB188 -- using a near-infrared (NIR) extinction technique applied to 2MASS photometry, combined with stellar distances from \textit{Gaia} DR3 parallaxes. Extinction-distance profiles reveal distinct rises marking each cloud, yielding median distances of 766~pc (CB4), 354~pc (CB24), 483~pc (CB56), 1143~pc (CB60), and 926~pc (CB188). Weighted-mean values agree within $8.0\%$, supporting the internal consistency of the method and interquartile-range-based uncertainties span 3-9\% across the sample. Independent validation with Bayestar19 3D dust maps supports the CB4 and CB188 results. These refined distances provide an improved basis for future determinations of cloud masses, densities, and star-formation efficiencies, including the first robust measurement for CB56 and a revised upward distance for CB188.

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Rajat Subhra Paul, Himadri Sekhar Das. 2026-07-13. Distance Estimates to Five Bok Globules Using Gaia DR3 Parallaxes and Near-Infrared Photometry: Validation with 3D Dust Maps. https://arxiv.org/abs/2607.11080

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